Method and apparatus for producing wide webs from continuous multifilament yarns



July 14, 1970 Filed Dec. 7, 1967 F. KALWAITES ETAL 3,520,037

METHOD AND APPARATUS FOR PRODUCING WIDE WEBS FROM CONTINUOUSMULTIFILAMENT YARNS 4 Sheets-Sheet l INVENTORSZ BY Q y 1970 F. KALWAITESETAL METHOD AND APPARATUS FOR PRODUCING WIDE WEBS FROM CONTINUOUSMULTIFILAMENT YARNS 4 Sheets-Sheet 2 Filed D90. 7, 1967 IT QAS-INVENTORS: Fem K A444 /7's fP/vssz ATTORNEY.

y 1970 F. KALWAITES ETAL 3,

METHOD AND APPARATUS FOR PRODUCING WIDE WEBS FROM CONTINUOUSMULTIFILAMENT YARNS Filed D60- 7, 1967 4 Sheets-Sheet 3 INVENTORS: Fem/KA444 025s EPA/57 A nvaqs ATTO NEY.

14, 1970 F. KALWAITES ETAL 3,520,037

METHOD AND APPARATUS FOR PRODUCING WIDE WEBS FROM CONTINUOUSMULTIFILAMENT YARNS Filed Dec. 7. 1967 4 Sheets-Sheet 4 INVENTORS. FRANKA444 11/4/7219 EPA/5.5T A. Po/ 7,94 s

ATTOR EY.

United States Patent 3,520,037 METHOD AND APPARATUS FOR PRODUCING WIDE.WEBS FROM CONTINUOUS MULTI- FILAMENT YARNS Frank Kalwaites, Somerville,and Ernest L. Poitras, Cranbury, N.J., assignors to Johnson & Johnson, acorporation of New Jersey Filed Dec. 7, 1967, Ser. No. 688,857 Int. Cl.D02g l US. Cl. 28-1.5 11 Claims ABSTRACT OF THE DISCLOSURE A method andapparatus for producing wide webs from a plurality of continuousmultifilament yarns comprising moving a plurality of continuousmultifilament This invention relates to a method for producing webs orsheets of continuous filaments from a plurality of continuousmultifilament yarns and to apparatus for carrying out such a method.

Fibrous webs are made from staple length fibers and/ or short lengthpaper making fibers. Such webs are usually made by a card engine or bypaper making or air laying machines. These machines produce a sheet orweb of overlapping, intersecting, randomly arranged fibers. The web isheld together by the frictional entanglement of the fibers and is quiteweak. Nonwoven fabrics produced from these webs are usually produced byplying a number of webs together and applying adhesive to the laminateto bond it into a unitary structure.

The present invention contemplates a method for making a new type web ofcontinuous textile filaments. The filaments run the entire length of theWeb and may be relatively parallel or may be in various wavy typeconfigurations. Nonwoven fabrics may be produced by laminating sheets orwebs of these filaments together either parallel to each other or atangles to each other and if desired small amounts of adhesives may beapplied to hold the plies together. Fabrics produced from suchtechniques have great strength in the direction of the filamentalignment and also have a different hand and feel as compared to fabricsmade from staple length fibers.

The desirability of such a filament fabric has been known, however, wehave developed a method and apparatus for continuously, uniformlyproducing the base webs from which such fabrics may be produced.

In the fiber industry it is common practice to produce yarns fromcontinuous filaments. The synthetic materials are extruded through aspinerette in continuous lengths and go through the necessary drawingand orienting operations as are commonly known. These filaments may insome instances be cut in various lengths to produce staple fiber fromwhich which standard nonwoven fabrics or spun yarns are produced. Insome instances if the filaments are large enough they may be used bythemselves to produce a monofilament yarn and in still other instanceswhen the filaments are quite small in diameter a plurality of thesefilaments are bundled together as extruded and form what is commonlytermed a multifilament yarn. In some instances a twist may be 3,520,037Patented July 14, 1970 ice applied to those multifilament yarns toimprove the strength of the yarn. It is these multifilament yarns whichhave substantially zero twist from which we are able to produce webs ofcontinuous filaments in accordance with the method and apparatus of thepresent invention.

In accordance with the present invention we take a plurality of the zerotwist multifilament yarns and supply them in the same planesubstantially parallel to each other. We move this sheet of yarns in afirst path. We then change the direction in which this sheet of yarns ismoving to a second path with the second path making an angle with thefirst path of less than 70 degrees. While the yarns are moving in thesecond direction we place them under a draft of at least 2 percent. Thischange in direction coupled with the draft places a curl or crimp insubstantially all of the filaments of the yarns. The curled yarns arethen moved in a third path and while being so moved are intermittentlytensed and relaxed which disengages the curl in each filament from thecurl in adjacent filaments. The yarns are intermittently tensed andrelaxed a plurality of times to disengage filament curls and blend thefilaments of one yarn with the filaments of adjacent yarns to produce auniform wide sheet of continuous filaments.

In carrying our invention into practice the apparatus comprises meansfor supplying a layer of zero twist, continuous, multifilament yarns,said yarns being substantially parallel to each other and in the sameplane, means for moving the yarns in a first path, means for moving theyarns at an acute angle of less than 70 degrees, and means for applyinga draft to said yarns substantially immediately after the yarns passthrough said acute angle. Positioned substantially immediately aftersaid drafting means are means for intermittently tensing and relaxingsaid yarns a plurality of times whereby individual filaments disengagefrom adjacent filaments and the filaments of one yarn blend with thefilaments of adjacent yarns to form a web of continuous filaments.

The amount of draft applied to the yarns may vary from about 2 percentto 10 percent and preferably ranges from about 3 percent to 6 percent.These drafts place the yarns under sufficient tension so that whenproperly combined with passing'the yarns through an acute angle theyarns will curl. The draft is actually the difierence in lineal speedbetween two positions through which the yarn passes with the linealspeed of the second position being 2 percent to 10 percent faster thanthe lineal speed of the first. The amount of tension applied to the yarnwill vary dependent upon the amount of elongation the filaments have. Inany event, the maximum amount of tension applied should not be greaterthan 60 percent of the breaking strength of the yarn. Generally thelower the percent elongation of the yarn the lower the amount of tensionrequired, e.g., with rayon yarns having 14 percent elongation tensionsas low as 4 percent of the yarn breaking strength will suffice to curlthe yarns. Yarns having 18 to 25 percent elongation require tensions offrom about 10 to 15 percent of the yarn breaking strength in order toproduce a curl in the yarn. The optimum tension for most yarns is fromabout 25 percent to 35 percent of the breaking strength of the yarn.

The invention will be more fully understood from the description whichfollows taken in conjunction with the accompanying drawings in which:

FIG. 1 is a schematic top view of apparatus for carrying the presentinvention into practice;

FIG. 2 is a schematic side view of the apparatus of FIG. 1;

FIG. 3 is a schematic top view of another form of apparatus for carryingthe present invention into practice;

FIG. 4 is a schematic side view of the apparatus of FIG. 3;

FIG. 5 is a schematic top view of still other apparatus for carrying thepresent invention into practice;

FIG. 6 is a schematic side view of the apparatus of FIG. 5;

FIG. 7 is an enlarged cross-sectional view of the curling or crimpingapparatus as depicted in FIGS. l and 2;

FIG. 8 is an enlarged cross-sectional view of the curling and crimpingapparatus depicted in FIGS. 3 and 4;

FIG. 9 is an enlarged cross-sectional view of the tensing and relaxingapparatus depicted in FIGS. 2 and 6.

Referring to the drawings in FIGS. 1 and 2 there is shown a bank 20 ofyarn packages 21. The yarn is continuous multifilament yarn preferablywith zero twist or low twist. The yarns are drawn from the packagesthrough a spacer comb 22 to maintain the yarns in substantially the samehorizontal plane and approximately equally spaced apart. The spacedyarns are passed between the nip formed by a pair of rotating rolls 23and 24. The rolls are mounted in suitable stands 25 and 26- and aremounted for rotation in these stands by standard bearings, etc. Thesheet of yarns then passes between the nip of a rotatable roll 27 and astationary blade 28. The blade is in contact with the roll over theentire length of the roll, that is on a line parallel to the roll axis.The roll and blade are suitably mounted in framing 29. The yarns pass toa second pair of rotatable rolls 30 and 31 mounted for rotation insuitable framing 32. The speed of these rolls 30 and 31 is greater thanthe speed of the rotatable roll 27. The yarn then passes between the nipformed by a fluted roll 33 and a rotatable roll 34. Both the fluted androtatable rolls are mounted for rotation in suitable framing 35. Thefluted roll intermittently passes the yarn when the raised portion ofthe roll is in line with the surface of the rotatable roll and allowsthe yarn to relax in the recessed areas. The web is then placed on aconveyor 36 for bonding in further processmg.

In operation as the yarn passes about the edge of the stationary bladeit is placed under considerable tension by the pair of nip rolls 30 and31 and when this yarn passes through these nip rolls and this tension isrelaxed intermittently the yarn curls and the intermittent tensing andrelaxing of the yarn causes the curl in adjacent individual filaments ofa multifilament yarn to disengage and get out of registry and merge intofilaments of adjacent yarns to form a web or sheet of individualcontinuous filaments which are uniformly intermingled throughout thesheet.

Referring to FIGS. 3 and 4 there is shown a bank 40 of packages 41containing multifilament, zero twist yarns 42. The yarns are fed througha spacer 43 to form a sheet of parallel multifilament yarns. This sheetis passed between a pair of nip rolls 44 and 45 mounted for rotation insuitable framing 46. The sheet passes over a stationary nip blade 47also mounted in this framing 46 and through a second set of nip rolls 48and 49 mounted for rotation in the framing 46. The second set of niprolls is rotating faster than the first set of niprolls. The sheetpasses to a third set of hip rolls 50 and 51 running just slightlyslower than the speed of the second set of nip rolls. As it passesbetween these two sets of nip rolls it is intermittently contacted witha beater mechanism 52. The beater mechanism comprises a rotatable roll53 mounted for rotation in suitable framing 54 and extending outwardlyfrom this rotatable roll are 4 bars 55. These bars are mounted on rods56 extending outwardly from the center roll 53. The beater mechanismintermittently tenses and relaxes the filaments as they move from thenip of rolls 48 and 49 to the nip of rolls 50 and 51. Rolls 50 and 51should have a slightly faster peripheral linear speed than rolls 48 and49 to prevent slack from building up in yarns as they are beingconveyed.

This beater mechanism causes the curled filaments to disengage fromadjacent curled filaments and become entangled with the filaments ofadjacent yarns to form a continuous sheet of interengaged filamentswhich is placed on a conveyor 57 for further processing.

Referring to FIGS. 5 and 6 there is shown yet another apparatus forcarrying the present invention into practice. A bank 60 of packages 61of zero twist, continuous multifilament yarns 62 is shown. The yarns aredrawn from the package through a spacer comb 63 to form a sheet ofsubstantially equally spaced continuous multifilament yarns. This sheetis passed about a portion of the periphery of the nip roll 64 around thesharp edge of the blade 65 and between this blade and a second roll 66.The rolls 64 and 66 rotate in the same direction and are mounted forrotation in bearings mounted in the frame 67. Roll 66 rotates slightlyfaster than roll 64. The blade 65 is also mounted in the frame 67. Asmaller roll 68 also mounted for rotation in bearings in the framemaintains the yarns in contact with the surface of the roll 64 toprovide a uniform feed to the blade. The filaments continue in theirpath to a pair of nip rolls 69 and 70 mounted for rotation in bearingsmounted in suit able framing 71. This set of nip rolls is rotatingfaster than the roll 66. The sheet of filaments then passes between afluted roll 72 and smooth surfaced roll 73. These rolls 72 and 73 aremounted for rotation in bearings mounted in suitable framing 74. Thefluted roll alternately tenses and relaxes the sheet of filaments andcauses individual filaments of the yarn to disengage with adjacentfilaments to form a web of continuous interengaged filaments. The web isplaced on conveyor 75 for further processing.

Referring to FIG. 7 there is shown one type of curling mechanism of theapparatus of the present invention. In tangential contact along a lineparallel to the axis of a rotatable roll is a stationary blade 81. Thisblade is mounted in a suitable spring mounting means 82 so that it maybe forced with some pressure against the surface of the roll. The rollis preferably a medium rubber having a Durometer of from about 50 to 75.Mounted a short distance forwardly of the blade is a pair of rotatablenip rolls 83 and 84. These rotatable nip rolls rotate slightly fasterthan the first roll. The sheet of yarns pass between the roll and theblade and about the edge of the blade to the nip of the rotating rolls.By this technique the yarns are curled or crimped. The draft betweennips A and B shown must be greater than 2 percent and the angle on atwhich the yarn passes about the blade must be less than 70 degrees. Itis desirable that there be a finite distance C between the nip formed bythe blade and the first roll and the edge of the blade. The reason forthis is that if the blade edge is on the resilient surface of the rollit will tend to become indented in the surface and cause filamentbreakage. Distances of from about Ms inch to A inch have been foundsatisfactory in curling polyester and rayon yarns.

Referring to FIG. 8 there is shown another curling apparatus comprisinga first set of nip rolls and 91 rotating in the direction of the arrowsshown and a second set of nip rolls 92 and '93 rotating slightly fasterthan the first set and rotating in the direction of the arrows shown.Mounted between the two sets of nip rolls is a stationary blade 94. Theblade is mounted out of alignment of the two nips D and E. A sheet ofcontinuous filament yarns is passed between the first nip up and overthe blade into the second nip. This arrangement has been foundsatisfactory for crimping polyester and rayon yarns. The second set ofnip rolls must have a surface linear speed of at least 2 percent greaterthan the surface linear speed of the first set of nip rolls. Thedistance F that the blade must be from a line between the two nips mayrange from about Ms inch to a couple of inches or even greater. Theimportant thing is that the angle B at which the yarn passes and goesover the blade must be 70 degrees or less. In operation the importantpoints on the curling of the yarn are that the yarn must pass through apath that is at an acute angle to itself of 70 degrees or less and theyarn either as it passes through this angle or immediately after passingthrough this angle must be under tension and have at least 2 percentdraft. With these two criteria the mechanism will curl or crimppolyester, polyamide, acrylic, rayon, or other synthetic polymer orartificial multifilament yarns.

The blades described in accordance with the present invention may be ofvarious rigid or semi-rigid materials such as steel, preferably springsteel or other various plastic materials. Blades having a thickness of.020 inch have been found suitable for use in accordance with thepresent invention. The edge of the'blade may be straight or it may bebeveled on either or both sides.

Another modification of the apparatus is to heat the yarn as it ispassing about the blade to aid in the curling operation. The amount ofheat will, of course, depend upon the type of yarn being treated. Suchtemperatures may vary from about room temperature to about 430 F. Thetemperature should not be so high as to overly soften the yarn as it isbeing treated. The heating of polyester yarns improves the curlingoperation and tends to set the curl in the yarn. The heating of rayonyarns reduces the moisture content of the yarn and the humidity aroundthe yarn to give better curling.

After being curled the yarns are intermittently tensed and relaxed.Referring to FIG. 9 there is shown a simple mechanism for tensing andrelaxing the yarns. This mechanism comprises a pair of rolls. Theserolls are rotatable in the direction of the arrows shown. The upper roll100 has flutes 101 over its entire surface so that as a high area 102contacts the bottom roll 103 the yarns passing between the rolls aremoved forwardly whereas when a recessed area aligns with the axis of thebottom roll the yarns are allowed to relax. This action of the mechanismalternately tenses and relaxes the curled multifilament yarns aplurality of times which forces the individual filaments of the yarn todisengage with adjacent filaments of that same yarn and merge withadjacent individual filaments of adjacent yarns into a web ofinterengaged continuous filaments. The fluted rolls should have aperipheral linear speed such as to prevent slack from building up as thesheet of filaments is being processed.

Another mechanism for applying this alternate tensing and relaxing ofthe yarns has been previously described in conjunction with FIGS. 3 and4. Furthermore, if desired, more than one mechanism for tensing andrelaxing the yarns may be put in series to further separate individualfilaments from each other and merge them into a helter-skelter patternor web of filaments.

Multifilament yarns used in accordance with the present invention may beof any of the various synthetic filaments such as rayon, the polyamides,the polyesters, the polyolefins, etc. The denier of the individualfilaments may vary from about 2 denier up to 20 denier or higher and theyarns may contain anywhere from about 10 to 200 filaments or more.

Although all of the various holders. pulleys, belts, beaters, or likemechanical means including suitable framing have not been illustratedcompletely in the drawings or described in the specification for drivingor supporting the various rotating cylinders, roll, beaters, at theirdesired or required speeds or with the rotation or movement indicated bythe direct arrows it is to be appreciated that such elements have beenomitted to keep the drawings and descriptions distinct and to avoid theintroduction of matters which are well known expedients in the art. Themechanical driving means and various frames which are used areconventional and merely involve the application of well known mechanicalprinciples.

The invention will be further illustrated in greater detail by thefollowing specific examples.

6 EXAMPLE I Twenty four mutifilament, zero twist rayon yarns are placedin a parallel, horizontal plane with the yarns approximately inch apart.The yarns used are 600 total denier per yarn and 4 denier per filament.The parallel plane of twenty-four yarns is passed through the apparatusdepicted in FIGS. 1 and 2. The yarns are taken from suitable packagesdrawn through a spacer comb to form the plane of the yarns, which is fedthrough the first set of nip rolls. The yarn is then passed through thesingle stationary roll and blade unit, and from there to the second setof nip rolls. The second set of nip rolls rotates 5 percent faster thanthe roll in contact with the stationary blade. The angle that the yarnmakes with the blade as it passes about the blade is approximately 30degrees. The single roll has a rubber surface (Durometer 65). The bladeis spring steel and has a thickness of .020 inch. The parallelmultifilament yarns after passing through the blade and roll and to thesecond set of nip rolls is substantially uniformly curled. The yarnspass from the second set of nip rolls to the nip formed by a fluted rolland a smooth surface roll and are intermittently relaxed and tensed aplurality of times to merge individual filaments to a uniform web ofindividual continuous filaments arranged in a general helter-skelterpattern but aligned in the length of the web so formed.

EXAMPLE II Twenty-seven multifilament, zero twist rayon yarns are placedin a parallel horizontal plane with the yarns approximately Ainch apart.The yarns used are total denier per yarn and 3.6 denier per filament.The parallel plane of the twenty-seven yarns is passed to the apparatusdepicted in FIGS. 3 and 4. The yarns are taken from suitable packagesand drawn through a spacer comb to form the plane of yarns and fed tothe curling mechanism. The curling mechanism comprises a first set ofnip rolls and a second set of nip rolls with a stationary blade placedtherebetween but out ofthe line between the two nips. The yarns passthrough the first set of nip rolls about the blade and through thesecond set of nip rolls. The second set of nip rolls rotate atapproximately 3 percent faster than the first set of rolls. The blade isspring steel and has a thickness of .020 inch. The distance between theline between the nips at the top of the blade is approximately one inch.The angle which the yarn makes as it passes about the blade isapproximately 60 degrees. The parallel multifilament yarns after passingthrough the second pair of nip rolls are substantially uniformly curled.The yarns then pass through another set of nip rolls. Between the secondand third pair of nip rolls there is a beater roll as shown in thedrawings. As the beater roll rotates the filaments are alternatelystretched and relaxed. This action separates and individualizes thefilaments and merges them into a uniform web of continuous filaments.

EXAMPLE HI Twenty-four multifilament, zero twist polyester yarns areplaced in a parallel, horizontal plane with the yarns approximately inchapart. The yarns used are 670 total denier per yarn, 13 denier perfilament. The parallel plane of 24 yarns is passed to the apparatusdepicted in FIGS. 5 and 6. The yarns are taken from suitable packagesand drawn through a spacer comb to form the plane of yarns which is fedto the double roll and blade unit. A uniform tension is placed on theyarns as they are fed to the blade unit. The uniform tension is providedby the small roll in contact with the input roll. The input roll is asteel roll having a sandblasted surface. The second roll has a rubbercovered surface with the rubber having a Durometer hardness ofapproximately 50. The blade is spring steel and has a thickness 7 of.020 inch and a beveled edge. The beveled edge contacts the surface ofthe steel roll and the other edge contacts the rubber roll. The yarnsare drafted about 3 percent as they .pass through the mechanism. Theparallel multifilament yarns after passing through the blade and pair ofrolls are substantially uniformly curled and passed through a pair ofnip rolls under a minimum of tension. The minimal tension is sufficientto prevent sagging of the curled yarns. From this pair of nip rolls theyarns are passed to a third pair of nip rolls consisting of a rubberroll and a steel roll. The rubber roll has flutes on its surface. Theserolls intermittently tense and relax the filaments which separates thefilaments and merges them into a uniform web. A uniform web weighingapproximately 150 grains per square yard and comprising individualcontinuous filament yarns in a helterskelter :pattern is formed.

Although several specific examples of the inventive concept have beendescribed for purposes of illustration, the invention should not beconstrued as limited thereby nor to the specific features mentionedtherein. It is understood that changes, modifications, variations, maybe made in the method and apparatus as herein described withoutdeparting from the spirit and scope of the invention.

What is claimed is:

1. A method of producing a web of individual filaments arranged in anoverlapping, interengaging, intersecting layer of individual continuousfilaments comprising, continually moving a plurality of continuousfilament, zero twist yarns arranged in a plane in a first path and at afirst speed, changing the direction at which the said yarns are movingto a second path making an angle of less than 70 degrees with thedirection of said first path by directiing the yarns over a member whilesimultaneously increasing the speed at which the yarns are moving atleast 2 percent of the first speed to apply tension to said yarns,whereby stresses are placed in the yarn to impart a tendency in the yarnto curl, removing said tension whereby a series of curls are formed inthe yarns and applying intermittent tensing and relaxing forces to theyarns whereby the curls of the individual filaments are placed out ofregistry and the individual filaments merge into a uniform web ofcontinuous filaments.

2. A method according to claim 1 wherein the speed is increased fromabout 2 percent to percent of the first speed.

3. A method according to claim 1 wherein the speed is increased fromabout 3 percent to 6 percent of the first speed.

4. Apparatus for producing a web of interengaged, continuous filaments,comprising, supply means for supplying a plurality of continuousmultifilament, zero twist yarns, spacing means for arranging the yarnsin a plane of substantially parallel, spaced apart multifilament yarns,means including a member over which the yarns are passed for moving theyarns in an angular direction of less than 70 degrees, means forincreasing the speed of the yarns at least 2 percent while moving insaid angular direction to apply tension to said yarns, whereby stressesare placed in the yarn to impart a tendency in the yarns to curl andmeans for removing said tension and applying intermittent tensioningforces to the plurality of yarns whereby a curl is placed in the yarnswhen the tension is removed and individual filaments in each yarn aredisengaged with adjacent filaments and merge with fllaments or adjacentyarns when the intermittent tensioning forces are applied to produce aweb of filaments.

5. Apparatus according to claim 4 wherein the means for moving the planeof yarns in an angular direction and increasing the speed of the yarnscomprises, a first rotatable roll, a stationary blade constituting thememher in line contact with the surface of the first rotatable roll toform a nip therebetween through which the plane 8 of yarns is passed anda pair of nip rolls rotating at a faster peripheral linear speed thansaid first rotatable roll and spaced from said first roll and blade andin a lower horizontal plane than said first roll and blade.

6. Apparatus according to claim 4 wherein the means for moving the planeof yarns in an angular direction and increasing the speed of the yarnscomprises, two pair of rotatable nip rolls, means for rotating thesecond pair of nip rolls at a faster peripheral linear speed than firstpair, said pairs of nip rolls being in the same horizontal plane and astationary blade constituting the member positioned between said pairsof nip rolls but above such horizontal plane whereby the yarns pass fromthe first set of nip rolls upwardly about the edge of the blade and downinto the second set of nip rolls.

7. Apparatus according to claim 4 wherein the apparatus for moving theplane of yarns in an angular direction and increasing the speed of theyarns comprises, a pair of rotatable rolls, the axis of said rolls beingparallel and the rolls positioned with respect to each other to form anip between the rolls and having a minimum clearance between the rollsat the nip, means for rotating the rolls in the same direction and atdifferent linear surface speeds, a blade constituting the memberpositioned adjacent the nip and extending parallel to the axis of saidrolls, said blade being in contact with the surface of both of saidrolls.

8. Apparatus according to claim 4 wherein the means for removing thetension and applying intermittent tensioning forces to place a curl inthe stressed yarns comprises, a pair of nip rolls spaced from the meansfor increasing the speed of the yarns and in the same horizontal plane,a beater roll comprising a rotating member and at least two barsattached to said member parallel to the axis of the said rotating memberand spaced therefrom, said rotating member being positioned so that thebars move through the path in which said plurality of yarns are passingwhereby the yarns are intermittently tensioned and relaxed to place acurl in the filaments of the yarns and deregister the curl in thefilaments of each yarn and merge filaments with adjacent filaments ofadjacent yarns.

9. Apparatus according to claim 4 wherein the means for removing thetension and applying intermittent tensioning forces to place a curl inthe stressed yarn comprises, a pair of nip rolls one of said rollshaving flutes on its surface parallel to the axis of the roll and theother of said rolls having a smooth surface whereby yarns passingthrough the nip of said pair of rolls are intermittently tensioned andrelaxed to place a curl in the filaments of the yarns and deregister thecurl in the filaments of each yarn and merge filaments with adjacentfilaments of adjacent yarns.

10. Apparatus for producing a Web of interengaged, continuous filamentscomprising, supply means for supplying a plurality of continuousmultifilament, zero twist yarns, spacing means for arranging the yarnsin a plane of substantially parallel, spaced apart multifilament yarns,a rotatable roll and a stationary blade in tangential contact with thesurface of said rotatable roll along a line parallel to the axis of saidroll to form a nip therebetween, said rotatable roll and bladepositioned to accept the plane of parallel yarns from said spacingmeans, a first pair of rotatable nip rolls positioned forwardly of andbeneath the nip formed by said rotatable roll and blade to change thedirection in which the yarns are moving, means for rotating said firstpair of rotatable nip rolls at a faster peripheral linear speed than theperipheral linear speed of said rotatable roll to apply tension to theyarns as they change direction and a second pair of rotatable nip rollspositioned to accept the plane of yarns from said first pair ofrotatable nip rolls, one of said rolls of said second pair having fluteson its surface parallel to the axis of the roll and the other roll ofsaid second pair having a smooth surface to remove the ten sion and formcurls in the yarns and to intermittently tension the curled yarns todisengage adjacent filaments and merge them with filaments of adjacentyarns to form a web.

11. Apparatus for producing a web of interengaged continuous filamentscomprising, supply means for supplying a plurality of continuousmultifilament, zero twist yarns, spaced means for arranging said yarnsin a plane of substantially parallel spaced apart multifilament yarns, afirst set of rotatable nip rolls, a second set of rotatable nip rolls,the nips of said first and second set being in the same horizontalplane, a stationary blade positioned between said first and second setsand having a free edge extending above said horizontal plane whereby theyarns change direction as they pass from said first set of rolls overthe blade to said second set of rolls, means for rotating said secondset of nip rolls at a faster peripheral linear speed than the peripherallinear speed of said first set to apply tension to the yarns as theypass over said blade, and a third set of rotatable nip rolls positionedto accept yarns from said second set of rotatable nip rolls, one of saidrolls of said third set having flutes on its surface parallel to theaxis of said roll and the other roll of said third set having a smoothsurface, to remove the tension and form curls in the yarns and tointermittently tension the curled yarns to disengage adjacent filamentsand merge them with filaments of adjacent yarns to form a web.

References Cited UNITED STATES PATENTS 2,022,854 12/ 1935 Greenwood.2,115,313 4/1938 Matthew et a1. 2,215,112 9/1940' Van Beck et al.2,244,203 6/ 1941 Kern. 2,247,504 7/1941 Kern. 2,790,208 4/1957 Smith.3,017,309 1/1962 Crawford et a1. 3,175,348 3/1965 Block 281.5 XR3,340,576 9/1967 Pannill et al. 3,376,609 4/ 1968 Kalwaites. 3,392,4257/ 1968 Kalwaites.

ROBERT R. MACKEY, Primary Examiner US. Cl. X.R.

